Pietro: OpenSSL seems to provide add, double, invert and multiply routines for EC points. There does not seem to be an explicit routine for subtract in the include files.
The book "Implementing Eliptic Curve Cryptography" by Michael Rosing has routines esub and poly_esub for doing a subtraction of two EC points depending on the type of underlying curve. Essentially these routines first perform a negation of the subtrahend followed by an addition. Bill -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Pietro Albano Sent: July 4, 2008 10:17 AM To: openssl-users@openssl.org Subject: Subtract betwen two EC_POINT Hi all, I'm newby on openssl coding, I developing Elgamal chiper , i need subtract two EC_POINT who can help me? ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager [EMAIL PROTECTED] ______________________________________________________________________ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager [EMAIL PROTECTED]
